Various types of expandable chucks and/or devices of similar character are known for use in connection with the reception of a reel member upon which either a web of material already has been wound and is to be unwound therefrom or upon which the web of material is to be wound. In one class of such devices, an expandable member is used to engage the core or reel to thereby securely hold same while the winding or unwinding operation proceeds. Furthermore, means are provided for expanding and allowing contraction of the expandable member to mount and demount the core or reel. Such means can, for example, be a sliding wedge device, cam device or the like. Such devices, however, generally are of complicated construction, expensive to make from the standpoint of the machining and labor involved to produce same, and somewhat limited to the degree with which the expandable member can be expanded so as to serve for use with cores or reels over a range of inside diameters of the latter.
Representative of devices of the type with which the present invention is concerned, are those described in U.S. Pat. Nos. 441,476; 533,451; 967,334; 1,016,738; 2,352,580; 2,456,893; 2,717,128; 2,733,873; 2,941,745; 2,942,892; and 4,079,896.